Ferrostatin-1 alleviates cerebral ischemia/reperfusion injury through activation of the AKT/GSK3β signaling pathway

Exploring the association between aging, ferroptosis, and common age-related diseases

Aging is a natural biological process that is characterized by the progressive decline in physiological functions and an increased vulnerability to age-related diseases. The aging process is driven by different cell and molecular mechanisms. It has recently been shown that aging is associated with heightened vulnerability to ferroptosis (an intracellular iron-dependent form of programmed cell death). This susceptibility arises from various factors including oxidative stress, impaired antioxidant defences, and dysregulated iron homeostasis. The progressive decline in cellular antioxidant capacity and the accumulation of damaged components contribute to the increased susceptibility of aging cells to ferroptosis. Dysregulation of key regulators involved in ferroptosis, such as glutathione peroxidase 4 (GPX4), iron regulatory proteins, and lipid metabolism enzymes, further exacerbates this vulnerability. The decline in cellular defence mechanisms against ferroptosis during aging contributes to the accumulation of damaged cells and tissues, ultimately resulting in the manifestation of age-related diseases. Understanding the intricate relevance between aging and ferroptosis holds significant potential for developing strategies to counteract the detrimental effects of aging and age-related diseases. This will subsequently act to mitigate the negative consequences of aging and improving overall health in the elderly population. This review aims to clarify the relationship between aging and ferroptosis, and explores the underlying mechanisms and implications for age-related disorders, including neurodegenerative, cardiovascular, and neoplastic diseases. We also discuss the accumulating evidence suggesting that the imbalance of redox homeostasis and perturbations in iron metabolism contribute to the age-associated vulnerability to ferroptosis.

Exploring the molecular interactions between ferroptosis and the Wnt/β-catenin signaling pathway: Implications for cancer and disease therapy

Ferroptosis, a regulated form of cell death dependent on iron and marked by lipid peroxidation, is increasingly recognized for its role in a wide array of diseases, including cancers, neurodegenerative disorders, and tissue damage. This review examines the dynamic interaction between ferroptosis and the Wnt/β-catenin signaling pathway, focusing on how Wnt surface receptors, ligands, antagonists, and associated components influence the regulation of ferroptosis. Key elements such as Frizzled receptors, Wnt ligands, and antagonists like DKK1 are shown to affect ferroptosis by altering oxidative stress, lipid dynamics, and iron metabolism. A central aspect of this interaction is the role of the destruction complex, particularly GSK-3β, which regulates ferroptosis through its upstream modulation by the AKT pathway and downstream control over NRF2, GPX4, and SLC7A11. Furthermore, the involvement of β-catenin/TCF transcription factors in the regulation of ferroptosis emphasizes the significance of this pathway in promoting cell survival and resisting ferroptosis, particularly in various cancers. Multiple cancers, including colorectal, breast, ovarian, and lung cancers, are affected by disruptions in the Wnt/ferroptosis axis, where enhanced Wnt signaling helps cancer cells evade ferroptosis and develop resistance to treatments. Beyond cancer, this axis also plays a crucial role in neurodegenerative diseases and conditions like myocardial infarction. Additionally, natural compounds have shown potential in modulating the Wnt/ferroptosis pathway, offering promising therapeutic approaches for a variety of diseases. This review highlights the molecular mechanisms of the Wnt/ferroptosis axis, paving the way for innovative treatment options in cancer and other diseases.

Inhibition of diacylglycerol O-acyltransferase 1 provides neuroprotection by inhibiting ferroptosis in ischemic stroke

BACKGROUND

Diacylglycerol O-acyltransferase 1 (DGAT1) is crucial for triglyceride synthesis, yet its role in ischemic stroke remains unclear. This study investigated DGAT1 in ischemic stroke using middle cerebral artery occlusion (MCAO) rat models and highly differentiated PC12 cells subjected to oxygen-glucose deprivation/reoxygenation (OGD/R).

METHODS

The therapeutic effects of DGAT1 inhibition in MCAO rats were assessed using the Zea-Longa score and 2,3,5-Triphenyltetrazolium chloride (TTC) staining. The effects on highly differentiated PC12 cells subjected to OGD/R were evaluated using the Cell Counting Kit-8 (CCK-8) and lactate dehydrogenase (LDH) assays. Ferroptosis-related mitochondrial damage was evaluated using transmission electron microscope. Additionally, the mechanisms by which DGAT1 inhibition regulates ferroptosis were further explored via immunohistochemistry, immunofluorescence, Western blotting, qPCR, JC-1 assay, and reactive oxygen species (ROS) detection.

RESULTS

DGAT1 expression was elevated in both MCAO and OGD/R models. The DGAT1 inhibitor A 922500 improved neurological deficits, reduced infarct volume, and minimized neuronal loss in MCAO rats, while also enhancing cell viability and reducing LDH levels in OGD/R-treated PC12 cells. DGAT1 inhibition significantly alleviated ferroptosis in MCAO rats, as indicated by (i) reduced mitochondrial shortening and cristae disruption, (ii) decreased 4-HNE levels, (iii) reduced MDA and increased SOD, and (iv) lowered levels of inflammatory factors (IL-6, MCP-1, and TNF-α). Moreover, both in vivo and in vitro experiments showed that DGAT1 inhibition significantly increased Gpx4 levels, whereas lentiviral delivery of Gpx4 shRNA markedly reversed its beneficial effects. In MCAO rats, Gpx4 shRNA significantly elevated 4-HNE levels and exacerbated ferroptosis-related mitochondrial damage. In vitro, DGAT1 inhibition increased mitochondrial membrane potential and reduced ROS, whereas rotenone, a mitochondrial function inhibitor, decreased Gpx4 and impaired cell viability. Furthermore, DGAT1 inhibition significantly upregulated the key β-oxidation gene Cpt1a, whereas etomoxir, a β-oxidation inhibitor, reduced cell viability and mitochondrial membrane potential, increased ROS, and downregulated Gpx4.

CONCLUSIONS

Our study suggests that DGAT1 inhibition may enhance β-oxidation and mitochondrial function, thereby increasing Gpx4 levels, suppressing ferroptosis, and ultimately exerting neuroprotective effects in ischemic stroke.

Mechanism of USP18-Mediated NCOA4 m6A Modification Via Maintaining FTO Stability In Regulating Ferritinophagy-Mediated Ferroptosis in Cerebral Ischemia-Reperfusion Injury

This study aimed to explore whether USP18 regulates cerebral ischemia-reperfusion (I/R) injury via fat mass and obesity-associated proteins (FTO)-mediated NCOA4. Middle cerebral artery occlusion (MCAO) models were established in mice, and PC-12 cells treated with oxygen-glucose deprivation and reperfusion (OGD/R) were used as in vitro models. The USP18 lentiviral vector was transfected into cells in vitro and MCAO mice to observe its effect on ferroptosis. The relationship between USP18 and FTO was assessed using Co-IP and western blot. The effect of FTO on NCOA4 m6A modification was also elucidated. Overexpression of USP18 in MCAO models decreased cerebral infarct size and attenuated pathological conditions in mouse brain tissues. Moreover, USP18 reduced iron content, MDA, ROS, and LDH release, increased GSH levels and cell viability in both MCAO models and OGD/R cells, and promoted LC3 expression and autophagy flux. In vitro experiments on neurons showed that USP18 maintained FTO stability. The presence of FTO-m6A-YTFDH1-NCOA4 was also verified in neurons. Both in vivo and in vitro experiments showed that FTO and NCOA4 abrogated the protective effects of USP18 against ferritinophagy-mediated ferroptosis. Notably, USP18 maintains FTO stability, contributing to the removal of NCOA4 m6A modification and the suppression of NCOA4 translation, which consequently inhibits ferritinophagy-mediated ferroptosis to attenuate cerebral I/R injury.

Cynaroside: a potential therapeutic agent targeting arachidonate 15-lipoxygenase to mitigate cerebral ischemia/reperfusion injury

Introduction

Due to the anti-inflammatory and antioxidant properties of cynaroside (Cyn), it may be useful in the treatment of cerebral ischemia/reperfusion injury (I/R). This study aims to evaluate the effect of Cyn on cerebral ischemia/reperfusion injury.

Methods

Transient middle cerebral artery occlusion model (tMCAO) and oxygen and glucose deprivation/reperfusion (OGD/R) microglia models were used to evaluate the effect of Cyn. The direct interaction between Cyn and Alox15 was investigated through bioinformatics, molecular docking and biolayer interferometry.

Results

tMCAO mice treated with Cyn show improved neurological deficits, reduced infarct volume and edema, and inhibition of microglial activation. In addition, Cyn inhibited tMCAO-induced Alox15 expression. Cyn significantly reduced the overproduction of the M1 microglia-regulated pro-inflammatory cytokines NLRP3, ASC, and cleaved caspase-1, as well as the overproduction of IL-1β and IL-18, induced by tMCAO or OGD/R. Cyn also inhibits the expression of Tfrc, COX2, and Acsl4 in tMCAO and OGD/R-treated mice and BV-2 cells.

Discussion

These results suggest that Cyn may attenuate cerebral ischemia/reperfusion injury by inhibiting Alox15 to reduce inflammation and reduce ferroptosis. This study reveals the underlying molecular mechanism of Cyn in the treatment of ischemic stroke.

Tetramethylpyrazine attenuates cerebral ischemia-reperfusion injury by inhibiting ferroptosis via the AMPK / Nrf2 pathways

OBJECTIVES

Ferroptosis is involved in the development and exacerbation of cerebral ischemia-reperfusion injury (CIRI), and its inhibition can alleviate CIRI. Tetramethylpyrazine (TMP) is used for the treatment of ischemic stroke. However, the mechanism by which TMP regulates ferroptosis in CIRI is yet to be explored. This study demonstrated the effects of TMP on ferroptosis and CIRI, including the roles of the adenosine 5'-monophosphate-activated protein kinase (AMPK)/nuclear factor erythroid-2-related factor 2 (Nrf2) signaling pathway.

MATERIALS AND METHODS

A Sprague-Dawley rat middle cerebral artery occlusion/reperfusion (MCAO/R) model was generated. The extent of neuronal injury was measured using 2,3,5-triphenyl tetrazolium chloride staining and Garcia neurological scoring and behavior was evaluated using open-field tests. Ferroptosis-related indexes were examined and ferroptosis-related proteins were detected using western blotting. The binding modes of TMP and AMPK were evaluated using molecular docking and molecular dynamics simulations.

RESULTS

MCAO/R rats showed a reduced cerebral infarct area and improved neurological function after TMP intervention. TMP reduced levels of Fe2+, 4-hydroxynonenal, malonaldehyde, and acyl-coenzyme synthetase long-chain family member 4 and increased levels of glutathione and glutathione peroxidase 4. Increased AMPK phosphorylation and Nrf2 expression were also detected. TMP bound tightly to the AMPKα subunit in silico, and the LEU157, VAL41, LEU33, VAL107, and TYR106 residues were important for binding.

CONCLUSIONS

Our results indicate that TMP can alleviate CIRI by inhibiting ferroptosis via the activation of the AMPK/Nrf2 pathway, providing a theoretical basis for the clinical use of TMP in treating CIRI.

Ferroptosis and cognitive impairment: Unraveling the link and potential therapeutic targets

Neurodegenerative disorders, such as Alzheimer's and Parkinson's diseases, share key characteristics, notably cognitive impairment and significant cell death in specific brain regions. Cognition, a complex mental process allowing individuals to perceive time and place, is disrupted in these conditions. This consistent disruption suggests the possibility of a shared underlying mechanism across all neurodegenerative diseases. One potential common factor is the activation of pathways leading to cell death. Despite significant progress in understanding cell death pathways, no definitive treatments have emerged. This has shifted focus towards less-explored mechanisms like ferroptosis, which holds potential due to its involvement in oxidative stress and iron metabolism. Unlike apoptosis or necrosis, ferroptosis offers a novel therapeutic avenue due to its distinct biochemical and genetic underpinnings, making it a promising target in neurodegenerative disease treatment. Ferroptosis is distinguished from other cellular death mechanisms, by distinctive characteristics such as an imbalance of iron hemostasis, peroxidation of lipids in the plasma membrane, and dysregulated glutathione metabolism. In this review, we discuss the potential role of ferroptosis in cognitive impairment. We then summarize the evidence linking ferroptosis biomarkers to cognitive impairment brought on by neurodegeneration while highlighting recent advancements in our understanding of the molecular and genetic mechanisms behind the condition. Finally, we discuss the prospective therapeutic implications of targeting ferroptosis for the treatment of cognitive abnormalities associated with neurodegeneration, including natural and synthetic substances that suppress ferroptosis via a variety of mechanisms. Promising therapeutic candidates, including antioxidants and iron chelators, are being explored to inhibit ferroptosis and mitigate cognitive decline.

An update on the role of ferroptosis in ischemic stroke: from molecular pathways to Neuroprotection

INTRODUCTION

Ischemic stroke (IS), a major cause of mortality and disability worldwide, remains a significant healthcare challenge due to limited therapeutic options. Ferroptosis, a distinct iron-dependent form of regulated cell death characterized by lipid peroxidation and oxidative stress, has emerged as a crucial mechanism in IS pathophysiology. This review explores the role of ferroptosis in IS and its potential for driving innovative therapeutic strategies.

AREA COVERED

This review delves into the practical implications of ferroptosis in IS, focusing on molecular mechanisms like lipid peroxidation, iron accumulation, and their interplay with inflammation, reactive oxygen species (ROS), and the Nrf2-ARE antioxidant system. It highlights ferroptotic proteins, small-molecule inhibitors, and non-coding RNA modulators as emerging therapeutic targets to mitigate neuroinflammation and neuronal cell death. Studies from PubMed (1982-2024) were identified using MeSH terms such as 'Ferroptosis' and 'Ischemic Stroke,' and only rigorously screened articles were included.

EXPERT OPINION

Despite preclinical evidence supporting the neuroprotective effects of ferroptosis inhibitors, clinical translation faces hurdles such as suboptimal pharmacokinetics and safety concerns. Advances in drug delivery systems, bioinformatics, and AI-driven drug discovery may optimize ferroptosis-targeting strategies, develop biomarkers, and improve therapeutic outcomes for IS patients.

MAM-mediated mitophagy and endoplasmic reticulum stress: the hidden regulators of ischemic stroke

Ischemic stroke (IS) is the predominant subtype of stroke and a leading contributor to global mortality. The mitochondrial-associated endoplasmic reticulum membrane (MAM) is a specialized region that facilitates communication between the endoplasmic reticulum and mitochondria, and has been extensively investigated in the context of neurodegenerative diseases. Nevertheless, its precise involvement in IS remains elusive. This literature review elucidates the intricate involvement of MAM in mitophagy and endoplasmic reticulum stress during IS. PINK1, FUNDC1, Beclin1, and Mfn2 are highly concentrated in the MAM and play a crucial role in regulating mitochondrial autophagy. GRP78, IRE1, PERK, and Sig-1R participate in the unfolded protein response (UPR) within the MAM, regulating endoplasmic reticulum stress during IS. Hence, the diverse molecules on MAM operate independently and interact with each other, collectively contributing to the pathogenesis of IS as the covert orchestrator.

The role of glutathione peroxidase 4 in neuronal ferroptosis and its therapeutic potential in ischemic and hemorrhagic stroke

Ferroptosis is a type of cell death that depends on iron and is driven by lipid peroxidation, playing a crucial role in neuronal death during stroke. A central element in this process is the inactivation of glutathione peroxidase 4 (GPx4), an antioxidant enzyme that helps maintain redox balance by reducing lipid hydroperoxides. This review examines the critical function of GPx4 in controlling neuronal ferroptosis following ischemic and hemorrhagic stroke. We explore the mechanisms through which GPx4 becomes inactivated in various stroke subtypes. In strokes, excess glutamate depletes glutathione (GSH) and products of hemoglobin breakdown overwhelm GPx4. Studies using genetic models with GPx4 deficiency underscore its vital role in maintaining neuronal survival and function. We also consider new therapeutic approaches to enhance GPx4 activity, including novel small molecule activators, adjustments in GSH metabolism, and selenium supplementation. Additionally, we outline the potential benefits of combining these GPx4-focused strategies with other anti-ferroptotic methods like iron chelation and lipoxygenase inhibition for enhanced neuroprotection. Furthermore, we highlight the significance of understanding the timing of GPx4 inactivation during stroke progression to design effective therapeutic interventions.

Blood brain barrier-targeted lipid nanoparticles improved the neuroprotection of Ferrostatin-1 against cerebral ischemic damage in an experimental stroke model

Cerebral ischemic stroke is a serious disease with high mortality and disability rates. However, few neuroprotective drugs have been used for ischemic stroke in the clinic. Two main reasons may be responsible for this failure: difficulty in penetrating the blood-brain barrier (BBB) and easily inactivated in the blood circulation. Ferroptosis, a lipid oxidation-related cell death, plays significant roles in cerebral ischemia-reperfusion injury. We utilized RVG29, a peptide derived from Rabies virus glycoprotein, to obtain BBB-targeted lipid nanoparticles (T-LNPs) in order to investigate whether T-LNPs improved the neuroprotective effects of Ferrostatin-1 (Fer1, an inhibitor of ferroptosis) against cerebral ischemic damage. T-LNPs significantly increased BBB penetration following oxygen/glucose deprivation exposure in an in vitro BBB model and enhanced the fluorescence distribution in brain tissues at 6 h post-administration in a cerebral ischemic murine model. Moreover, T-LNPs encapsulated Fer1 (T-LNPs-Fer1) significantly enhanced the inhibitory effects of Fer1 on ferroptosis by maintaining the homeostasis of NADPH oxidase 4 (NOX4) and glutathione peroxidase 4 (GPX4) signals in neuronal cells after cerebral ischemia. T-LNPs-Fer1 significantly suppressed oxidative stress [heme oxygenase-1 expression and malondialdehyde (the product of lipid ROS reaction)] in neurons and alleviated ischemia-induced neuronal cell death, compared to Fer1 alone without encapsulation. Furthermore, T-LNPs-Fer1 significantly reduced cerebral infarction and improved behavior functions compared to Fer1-treated cerebral ischemic mice after 45-min ischemia/24-h reperfusion. These findings showed that the T-LNPs helped Fer1 penetrate the BBB and improved the neuroprotection of Fer1 against cerebral ischemic damage in experimental stroke, providing a feasible translational strategy for the development of clinical drugs for the treatment of ischemic stroke.

The role of ferroptosis as a regulator of oxidative stress in the pathogenesis of ischemic stroke

Ferroptosis is a unique form of cell death that was first described in 2012 and plays a significant role in various diseases, including neurodegenerative conditions. It depends on a dysregulation of cellular iron metabolism, which increases free, redox-active, iron that can trigger Fenton reactions, generating hydroxyl radicals that damage cells through oxidative stress and lipid peroxidation. Lipid peroxides, resulting mainly from unsaturated fatty acids, damage cells by disrupting membrane integrity and propagating cell death signals. Moreover, lipid peroxide degradation products can further affect cellular components such as DNA, proteins, and amines. In ischemic stroke, where blood flow to the brain is restricted, there is increased iron absorption, oxidative stress, and compromised blood-brain barrier integrity. Imbalances in iron-transport and -storage proteins increase lipid oxidation and contribute to neuronal damage, thus pointing to the possibility of brain cells, especially neurons, dying from ferroptosis. Here, we review the evidence showing a role of ferroptosis in ischemic stroke, both in recent studies directly assessing this type of cell death, as well as in previous studies showing evidence that can now be revisited with our new knowledge on ferroptosis mechanisms. We also review the efforts made to target ferroptosis in ischemic stroke as a possible treatment to mitigate cellular damage and death.

Mechanism of ferroptosis regulating ischemic stroke and pharmacologically inhibiting ferroptosis in treatment of ischemic stroke

Ferroptosis is a newly discovered form of programmed cell death that is non-caspase-dependent and is characterized by the production of lethal levels of iron-dependent lipid reactive oxygen species (ROS). In recent years, ferroptosis has attracted great interest in the field of cerebral infarction because it differs morphologically, physiologically, and genetically from other forms of cell death such as necrosis, apoptosis, autophagy, and pyroptosis. In addition, ROS is considered to be an important prognostic factor for ischemic stroke, making it a promising target for stroke treatment. This paper summarizes the induction and defense mechanisms associated with ferroptosis, and explores potential treatment strategies for ischemic stroke in order to lay the groundwork for the development of new neuroprotective drugs.

Design and synthesis of sulfonamide phenothiazine derivatives as novel ferroptosis inhibitors and their therapeutic effects in spinal cord injury

Ferroptosis is a novel style of cell death, and studies have shown that ferroptosis is strongly associated with spinal cord injury (SCI). A large number of ferroptosis inhibitors have been reported, but so far no ferroptosis inhibitor has been used clinically. Therefore there is an urgent need to discover a better inhibitor of ferroptosis. In this study, 24 novel sulfonamide phenothiazine ferroptosis inhibitors were designed and synthesized, followed by structure-activity relationship studies on these compounds. Among them, compound 23b exhibited the best activity in Erastin-induced PC12 cells (EC50 = 0.001 μM) and demonstrated a low hERG inhibition activity (IC50 > 30 μM). Additionally, compound 23b was identified as a ROS scavenger and showed promising therapeutic effects in an SD rat model of SCI. Importantly, 23b did not display significant toxicity in both in vivo and in vitro experiments and show good pharmacokinetic properties. These findings suggest that compound 23b, a novel ferroptosis inhibitor, holds potential as a therapeutic agent for spinal cord injury and warrants further investigation.

Recent Advances and Therapeutic Implications of 2-Oxoglutarate-Dependent Dioxygenases in Ischemic Stroke

Ischemic stroke is a common disease with a high disability rate and mortality, which brings heavy pressure on families and medical insurance. Nowadays, the golden treatments for ischemic stroke in the acute phase mainly include endovascular therapy and intravenous thrombolysis. Some drugs are used to alleviate brain injury in patients with ischemic stroke, such as edaravone and 3-n-butylphthalide. However, no effective neuroprotective drug for ischemic stroke has been acknowledged. 2-Oxoglutarate-dependent dioxygenases (2OGDDs) are conserved and common dioxygenases whose activities depend on O2, Fe2+, and 2OG. Most 2OGDDs are expressed in the brain and are essential for the development and functions of the brain. Therefore, 2OGDDs likely play essential roles in ischemic brain injury. In this review, we briefly elucidate the functions of most 2OGDDs, particularly the effects of regulations of 2OGDDs on various cells in different phases after ischemic stroke. It would also provide promising potential therapeutic targets and directions of drug development for protecting the brain against ischemic injury and improving outcomes of ischemic stroke.

Panax notoginseng Saponins Activate Nuclear Factor Erythroid 2-Related Factor 2 to Inhibit Ferroptosis and Attenuate Inflammatory Injury in Cerebral Ischemia-Reperfusion

Panax notoginseng saponins (PNS), the primary medicinal ingredient of Panax notoginseng, mitigates cerebral ischemia-reperfusion injury (CIRI) by inhibiting inflammation, regulating oxidative stress, promoting angiogenesis, and improving microcirculation. Moreover, PNS activates nuclear factor erythroid 2-related factor 2 (Nrf2), which is known to inhibit ferroptosis and reduce inflammation in the rat brain. However, the molecular regulatory roles of PNS in CIRI-induced ferroptosis remain unclear. In this study, we aimed to investigate the effects of PNS on ferroptosis and inflammation in CIRI. We induced ferroptosis in SH-SY5Y cells via erastin stimulation and oxygen glucose deprivation/re-oxygenation (OGD/R) in vitro. Furthermore, we determined the effect of PNS treatment in a rat model of middle cerebral artery occlusion/reperfusion and assessed the underlying mechanism. We also analyzed the changes in the expression of ferroptosis-related proteins and inflammatory factors in the established rat model. OGD/R led to an increase in the levels of ferroptosis markers in SH-SY5Y cells, which were reduced by PNS treatment. In the rat model, combined treatment with an Nrf2 agonist, Nrf2 inhibitor, and PNS-Nrf2 inhibitor confirmed that PNS promotes Nrf2 nuclear localization and reduces ferroptosis and inflammatory responses, thereby mitigating brain injury. Mechanistically, PNS treatment facilitated Nrf2 activation, thereby regulating the expression of iron overload and lipid peroxidation-related proteins and the activities of anti-oxidant enzymes. This cascade inhibited ferroptosis and mitigated CIRI. Altogether, these results suggest that the ferroptosis-mediated activation of Nrf2 by PNS reduces inflammation and is a promising therapeutic approach for CIRI.

Crosstalk between autophagy and ferroptosis mediate injury in ischemic stroke by generating reactive oxygen species

Stroke represents a significant threat to global human health, characterized by high rates of morbidity, disability, and mortality. Predominantly, strokes are ischemic in nature. Ischemic stroke (IS) is influenced by various cell death pathways, notably autophagy and ferroptosis. Recent studies have increasingly highlighted the interplay between autophagy and ferroptosis, a process likely driven by the accumulation of reactive oxygen species (ROS). Post-IS, either the inhibition of autophagy or its excessive activation can escalate ROS levels. Concurrently, the interaction between ROS and lipids during ferroptosis further augments ROS accumulation. Elevated ROS levels can provoke endoplasmic reticulum stress-induced autophagy and, in conjunction with free iron (Fe2+), can trigger ferroptosis. Moreover, ROS contribute to protein and lipid oxidation, endothelial dysfunction, and an inflammatory response, all of which mediate secondary brain injury following IS. This review succinctly explores the mechanisms of ROS-mediated crosstalk between autophagy and ferroptosis and the detrimental impact of increased ROS on IS. It also offers novel perspectives for IS treatment strategies.

Ferrostatin-1 improves neurological impairment induced by ischemia/reperfusion injury in the spinal cord through ERK1/2/SP1/GPX4

Spinal cord ischemia/reperfusion injury (SCIRI) induced by artificial aortic occlusion for a while during aortic surgery is a serious complication, leading to paraplegia and even death. Ferroptosis in the nervous system has been confirmed to contribute to neuronal death induced by SCIRI. Therefore, we investigated the therapeutic benefits of ferrostatin-1 (Fer-1, a ferroptosis inhibitor) and explored the mechanism and target of Fer-1 in SCIRI. Our results demonstrate that intrathecal injection of Fer-1 had a strong anti-SCIRI effect, improved ferroptosis-related indices, increased neurological function scores and motor neuron counts, and reduced BSCB leakage and neuroinflammation levels in the anterior horn. We found that SCIRI significantly elevated the levels of several important proteins, including SP1, p-ERK1/2/ERK1/2, COX2, TFR1, SLC40A1, SLC7A11, cleaved Caspase 3, GFAP, and Iba1, while reducing FTH1 and GPX4 protein expression, with no effect on ACSL4 expression. Fer-1 effectively ameliorated the ferroptosis-related changes in these proteins induced by SCIRI. However, for p-ERK1/2 and SP1, Fer-1 not only failed to reduce their expression but also significantly enhanced it. Fer-1 was injected into sham operation rats, abnormal increases in p-ERK1/2/ERK1/2 and SP1 were observed, along with an increase in GPX4. Fluorescent double labeling revealed that SP1 and GPX4 were expressed in neurons and astrocytes. Inhibitors of the ERK pathway (SCH772984) and siRNA against SP1 (AV-sh-SP1) significantly decreased the increase in SP1 and GPX4 protein levels, fluorescent density of SP1 and GPX4 in neurons, and the number of SP1-positive and GPX4-positive neurons induced by Fer-1. SCH772984 but not AV-sh-SP1 significantly reversed the decrease in GFAP and Iba1 induced by Fer-1. In conclusion, our results indicate that Fer-1 inhibited ferroptosis in spinal cord anterior horn neurons, improving neurological impairment and BSCB damage after SCIRI through the ERK1/2/SP1/GPX4 signaling pathway in rats.

Electroacupuncture Suppresses Oxidative Stress and Ferroptosis by Activating the mTOR/SREBP1 Pathway in Ischemic Stroke

Ischemic stroke (IS) is one of the leading causes of death and disability worldwide. Electroacupuncture (EA) has been shown to exert a neuroprotective effect in IS. However, its specific anti-IS mechanisms remain to be fully elucidated. By constructing a rat IS (middle cerebral artery occlusion, or MCAO) model and performing EA treatment, neurological deficit score, brain water content, and cerebral infarction were evaluated. ELISA was used to measure the levels of oxidative stress-related molecules (MDA, SOD, GSH, and CAT). Ferroptosis-related proteins (GPX4, SLC7A11, TfR1, L-ferritin, and hepcidin), neurological damage-related proteins (GFAP, Iba-1, and Nestin), α7nAChR, and mTOR pathway-related proteins (mTOR, p-mTOR, and SREBP1) in the rat brain penumbra were assessed by western blotting. Following EA treatment, neurological deficit scores, brain water content, cerebral infarction area, and GFAP, Iba-1, and Nestin expression were reduced. Additionally, EA treatment decreased MDA and increased SOD, GSH, and CAT. Moreover, the rats showed elevated GPX4 and SLC7A11 and lowered TfR1, L-ferritin, and hepcidin. In contrast, a7nAChR, mTOR, p-mTOR, and SREBP1 expression were upregulated. EA treatment inhibited OS and ferroptosis to exert a neuroprotective effect in IS, which might be realized via the activation of mTOR/SREBP1 signaling.

Targeting epigenetic and posttranslational modifications regulating ferroptosis for the treatment of diseases

Ferroptosis, a unique modality of cell death with mechanistic and morphological differences from other cell death modes, plays a pivotal role in regulating tumorigenesis and offers a new opportunity for modulating anticancer drug resistance. Aberrant epigenetic modifications and posttranslational modifications (PTMs) promote anticancer drug resistance, cancer progression, and metastasis. Accumulating studies indicate that epigenetic modifications can transcriptionally and translationally determine cancer cell vulnerability to ferroptosis and that ferroptosis functions as a driver in nervous system diseases (NSDs), cardiovascular diseases (CVDs), liver diseases, lung diseases, and kidney diseases. In this review, we first summarize the core molecular mechanisms of ferroptosis. Then, the roles of epigenetic processes, including histone PTMs, DNA methylation, and noncoding RNA regulation and PTMs, such as phosphorylation, ubiquitination, SUMOylation, acetylation, methylation, and ADP-ribosylation, are concisely discussed. The roles of epigenetic modifications and PTMs in ferroptosis regulation in the genesis of diseases, including cancers, NSD, CVDs, liver diseases, lung diseases, and kidney diseases, as well as the application of epigenetic and PTM modulators in the therapy of these diseases, are then discussed in detail. Elucidating the mechanisms of ferroptosis regulation mediated by epigenetic modifications and PTMs in cancer and other diseases will facilitate the development of promising combination therapeutic regimens containing epigenetic or PTM-targeting agents and ferroptosis inducers that can be used to overcome chemotherapeutic resistance in cancer and could be used to prevent other diseases. In addition, these mechanisms highlight potential therapeutic approaches to overcome chemoresistance in cancer or halt the genesis of other diseases.

Pharmacological Inhibition of Ferroptosis as a Therapeutic Target for Neurodegenerative Diseases and Strokes

Emerging evidence suggests that ferroptosis, a unique regulated cell death modality that is morphologically and mechanistically different from other forms of cell death, plays a vital role in the pathophysiological process of neurodegenerative diseases, and strokes. Accumulating evidence supports ferroptosis as a critical factor of neurodegenerative diseases and strokes, and pharmacological inhibition of ferroptosis as a therapeutic target for these diseases. In this review article, the core mechanisms of ferroptosis are overviewed and the roles of ferroptosis in neurodegenerative diseases and strokes are described. Finally, the emerging findings in treating neurodegenerative diseases and strokes through pharmacological inhibition of ferroptosis are described. This review demonstrates that pharmacological inhibition of ferroptosis by bioactive small-molecule compounds (ferroptosis inhibitors) could be effective for treatments of these diseases, and highlights a potential promising therapeutic avenue that could be used to prevent neurodegenerative diseases and strokes. This review article will shed light on developing novel therapeutic regimens by pharmacological inhibition of ferroptosis to slow down the progression of these diseases in the future.

Attenuation of ferroptosis as a potential therapeutic target for neuropsychiatric manifestations of post-COVID syndrome

Coronavirus disease-19 (COVID-19), caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), is associated with the persistence of pre-existing or the emergence of new neurological and psychiatric manifestations as a part of a multi-system affection known collectively as "post-COVID syndrome." Cognitive decline is the most prominent feature among these manifestations. The underlying neurobiological mechanisms remain under intense investigation. Ferroptosis is a form of cell death that results from the excessive accumulation of intracellular reactive iron, which mediates lipid peroxidation. The accumulation of lipid-based reactive oxygen species (ROS) and the impairment of glutathione peroxidase 4 (GPX4) activity trigger ferroptosis. The COVID-19-associated cytokine storm enhances the levels of circulating pro-inflammatory cytokines and causes immune-cell hyper-activation that is tightly linked to iron dysregulation. Severe COVID-19 presents with iron overload as one of the main features of its pathogenesis. Iron overload promotes a state of inflammation and immune dysfunction. This is well demonstrated by the strong association between COVID-19 severity and high levels of ferritin, which is a well-known inflammatory and iron overload biomarker. The dysregulation of iron, the high levels of lipid peroxidation biomarkers, and the inactivation of GPX4 in COVID-19 patients make a strong case for ferroptosis as a potential mechanism behind post-COVID neuropsychiatric deficits. Therefore, here we review the characteristics of iron and the attenuation of ferroptosis as a potential therapeutic target for neuropsychiatric post-COVID syndrome.

Salvia miltiorrhiza Alleviates Memory Deficit Induced by Ischemic Brain Injury in a Transient MCAO Mouse Model by Inhibiting Ferroptosis

Salvia miltiorrhiza (SM) has been used in oriental medicine for its neuroprotective effects against cardiovascular diseases and ischemic stroke. In this study, we investigated the therapeutic mechanism underlying the effects of SM on stroke using a transient middle cerebral artery occlusion (tMCAO) mouse model. Our results showed that SM administration significantly attenuated acute brain injury, including brain infarction and neurological deficits, 3 days after tMCAO. This was confirmed by our magnetic resonance imaging (MRI) study, which revealed a reduction in brain infarction with SM administration, as well as our magnetic resonance spectroscopy (MRS) study, which demonstrated the restoration of brain metabolites, including taurine, total creatine, and glutamate. The neuroprotective effects of SM were associated with the reduction in gliosis and upregulation of inflammatory cytokines, such as interleukin-6 (IL-6) and Tumor necrosis factor-α (TNF-α), along with the upregulation of phosphorylated STAT3 in post-ischemic brains. SM also reduced the levels of 4-Hydroxynonenal (4-HNE) and malondialdehyde (MDA), which are markers of lipid peroxidation, induced by oxidative stress upregulation in the penumbra of the tMCAO mouse brain. SM administration attenuated ischemic neuronal injury by inhibiting ferroptosis. Additionally, post-ischemic brain synaptic loss and neuronal loss were alleviated by SM administration, as demonstrated by Western blot and Nissl staining. Moreover, daily administration of SM for 28 days after tMCAO significantly reduced neurological deficits and improved survival rates in tMCAO mice. SM administration also resulted in improvement in post-stroke cognitive impairment, as measured by the novel object recognition and passive avoidance tests in tMCAO mice. Our findings suggest that SM provides neuroprotection against ischemic stroke and has potential as a therapeutic agent.

Sevoflurane Postconditioning Attenuates Cerebral Ischemia-Reperfusion Injury by Inhibiting SP1/ACSL4-Mediated Ferroptosis

Sevoflurane is the most commonly used anesthetic in clinical practice and exerts a protective effect on cerebral ischemia-reperfusion (I/R) injury. This study aims to elucidate the molecular mechanism by which sevoflurane postconditioning protects against cerebral I/R injury. Oxygen-glucose deprivation/reperfusion (OGD/R) model in vitro and the middle cerebral artery occlusion (MCAO) model in vivo were established to simulate cerebral I/R injury. Sevoflurane postconditioning reduced neurological deficits, cerebral infarction, and ferroptosis after I/R injury. Interestingly, sevoflurane significantly inhibited specificity protein 1 (SP1) expression in MACO rats and HT22 cells exposed to OGD/R. SP1 overexpression attenuated the neuroprotective effects of sevoflurane on OGD/R-treated HT22 cells, evidenced by reduced cell viability, increased apoptosis, and cleaved caspase-3 expression. Furthermore, chromatin immunoprecipitation and luciferase experiments verified that SP1 bound directly to the ACSL4 promoter region to increase its expression. In addition, sevoflurane inhibited ferroptosis via SP1/ACSL4 axis. Generally, our study describes an anti-ferroptosis effect of sevoflurane against cerebral I/R injury via downregulating the SP1/ASCL4 axis. These findings suggest a novel sight for cerebral protection against cerebral I/R injury and indicate a potential therapeutic approach for a variety of cerebral diseases.